MQ-9 carbon monoxide Combustible gas sensor alarm Arduino

MQ-9 MQ9 Carbon Monoxide Gas Alarm Combustible Sensor Module For Arduino #39; #39; #39; #39;Feature: Suitable for home or factory gas leakage monitoring devices. Have better sensitivity to CARBON MONOXIDE, METHANE, LIQUEFIED PETROLEUM GAS. High quality dual-panel design, with power indicator and TTL signal output instructions. DO switching signal (TTL) output and AO analog signal output. TTL output valid signal is low. (When the output low signal is on, it can be directly connected micro-controller or relay module.) Analog output voltage: the higher concentration, the higher voltage. Four screw holes, easy positioning. Long life and stability, quick response and resume.